Cardiovascular disease (CVD) is the major cause of death in patients with chronic kidney disease (CKD). The few prospective epidemiologic studies that examined the relationship between dietary sodium and potassium intake and risk of CVD provided contradictory findings. Patients with CKD are likely to be more sensitive to sodium intake because their kidneys delay the excretion of sodium. This application is an ancillary study to the Chronic Renal Insufficiency Cohort (CRIC) Study. The CRIC study is an NIH-sponsored multi-center prospective cohort study that enrolled 3,689 adult patients with CKD (a glomerular filtration rate [GFR] from 20 to 70 ml/min based on patients'age) in the US and that will follow participants for up to 5 years. The overall objectives of the proposed study are to examine the cross-sectional and longitudinal relationships between dietary intake of sodium, potassium (estimated from multiple 24-hour urinary excretion), calcium, and magnesium (estimated from multiple food frequency questionnaires [FFQ]) and the risk of clinical CVD (including coronary heart disease [CHD], stroke, congestive heart failure [CHF], and peripheral arterial disease [PAD]) as well as the progression of sub-clinical CVD (coronary artery calcification score, left ventricular hypertrophy identified by Echo, and ankle-brachial index) among patients with CKD. We hypothesize that a higher dietary intake of sodium and lower intake of potassium, calcium, and magnesium are associated with an increased risk of clinical and sub-clinical CVD, CHD, stroke, CHF, and PAD, independent of other CVD risk factors including blood pressure, GFR, and dietary nutrients, among patients with CKD. The proposed study will contribute significantly to our understanding of the role of dietary sodium, potassium, calcium, and magnesium intake on the risk of CVD in patients with CKD and in the general population. The findings from this study will provide scientific evidence to develop preventive strategies for the reduction of dietary sodium intake and the moderate increase of dietary potassium intake in order to reduce the burden of CVD in CKD patients and in the general population. The few prospective epidemiologic studies that examined the relationship between dietary sodium and potassium intake and risk of cardiovascular disease provided contradictory findings. The overall objectives of the proposed study are to examine the cross-sectional and longitudinal relationships between dietary intake of sodium, potassium, calcium, and magnesium and the risk of clinical and sub-clinical cardiovascular disease (including coronary heart disease, stroke, congestive heart failure, and peripheral arterial disease) among 3,689 patients with chronic kidney disease. The findings from this study will provide scientific evidence to develop preventive strategies for the reduction of dietary sodium intake and the moderate increase of dietary potassium intake in order to reduce the burden of cardiovascular disease in chronic kidney disease patients and in the general population.